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The least positive term of an arithmetic progression whose first two terms are 5 2 and 23 12 is

Options

  1. A6
  2. B5
  3. C1 6
  4. D37 7

Correct answer

C. 1 6

Step-by-step solution

T n = 5 2 + n - 1 23 12 - 5 2 = 5 2 + n - 1 - 7 12 = 30 - 7 n + 7 12 T n > 0 ⇒ 37 - 7 n 12 > 0 ⇒ n < 37 7 ⇒ n = 5 T 5 = 37 - 35 12 = 1 6

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